Coastal Habitats Deemed Planet's Most Imperiled Ecosystems

Given their close proximity to the open ocean, it probably shouldn't come as a surprise that coastal habitats have been particularly damaged by the combined impact of climate change and anthropogenic development. At a recent debate on conservation biology organized by the BBVA Foundation, a group of international scientists presented their findings on the causes and consequences of the deterioration of coastal habitats (HINT: they weren't good).

Carlos Duarte, the debate's coordinator and a researcher at the Spanish Council for Scientific Researcher said that coastal habitats are "disappearing at a rate of between 1.2% and 9% a year and are now the biosphere's most imperiled systems, with rates of loss 4 to 10 ten times faster than those of the tropical rainforest." He ticked off a long list of causes, including "the rapidly growing population of coastal zones, currently home to 60% of the planet's inhabitants, along with the urban development, infrastructure works and ecosystem destruction this growth entails."In addition, he mentioned the effect climate change and eutrophication - which has become a larger concern because of the ever-increasing amounts of nitrogen, phosphorus and other organic matter being discharged in coastal areas around the world - were having in aggravating an already serious crisis. As a result, Scott Nixon, a professor at the University of Rhode Island, explained that "we are seeing a clear global increase in the incidence of hypoxia in coastal ecosystems."

"Global warming and the resulting rise in sea level are driving the loss and degradation of coastal habitats, reducing the effectiveness of conservation programs and causing an environmental problem of global dimensions which will also have a large economic impact on coastal societies," said Duarte.

Other findings included:• 54% of seagrass meadows have lost part of their coverage; those along the Spanish coast are losing close to 5% of their yearly extension.• 44% of the planet's coral reefs have disappeared or are about to.• 50% of coastal wetlands have been lost.• 35% of mangrove forests have been lost.